# std::atomic<T>::fetch_max

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< cpp‎ | atomic‎ | atomic

member only of `atomic<Integral`﻿`>` specializations |  |
T fetch_max( T arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; | (1) | (since C++26)
T fetch_max( T arg, std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; | (2) | (since C++26)
member only of `atomic<T*>` partial specialization |  |
T* fetch_max( T* arg, std::memory_order order = std::memory_order_seq_cst ) noexcept; | (3) | (since C++26)
T* fetch_max( T* arg, std::memory_order order = std::memory_order_seq_cst ) volatile noexcept; | (4) | (since C++26)

Atomically replaces the current value with the result of std::max of the value and arg. That is, it performs atomic maximum operation. The operation is a read-modify-write operation. Memory is affected according to the value of order.

3,4) If the pointers point to different complete objects (or subobjects thereof), pointer comparison does not establish a strict weak ordering.

It is deprecated if std::atomic<T>::is_always_lock_free is false and overload (2) or (4) participates in overload resolution.

### Parameters

arg | - | the other argument of std::max
order | - | memory order constraints to enforce

### Return value

The value immediately preceding the effects of this function in the modification order of *this.

### Notes

Feature-test macro | Value | Std | Feature
--- | --- | --- | ---
`__cpp_lib_atomic_min_max` | `202403L` | (C++26) | Atomic minimum/maximum

### Example

| This section is incomplete Reason: no example

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